Holding his son for the first time he reconsiders the life he lives. Thinks about what could actually happen and might. Blinking the thought goes away but it rears its head through out the rest of his life. Making him second guess. Only once does he wish for a few seconds to have made a different choice all those years ago.
When Harry turns two he isn't there to celebrate with Mary and his brothers. He wonders if he made the right choice with John. Wonders how many more birthdays and important dates he'll have to miss for the club. He wonders if he'll ever get the chance to actually be a father to his son.
When Marry leaves taking Opie with her, he's crushed. But as weeks go on he feels better. Maybe Opie will get to make a different choice then he did. Opie will get the life he didn't want. The life he truly could have never lived. Though as weeks turn to months, he can't but help the pang that Opie won't follow in his foot steps. That Opie won't know brotherhood like this.
The day Opie came though, he had never been so proud of his soon. Even if Opie truly didn't understand what it meant to be a Son all those years ago. He's happy his son followed his path. But he stops and wonders if Opie will have this thought floating in his head also.
He wonders if he'll ever settle this thought in his head. Wonders if he'll ever truly want to. Eventually he decides that this will simply haunt him until he takes his last breath.